Day Four
Making an HOn3 #6 code 55 turnout

To Review

Clean up the frog point assembly (I use a wedge shaped tapered mini file through
the frog flangeways.

Straight direction first put on the gauges and then solder in order

 

Then add the curved stock rail and solder three more places

 

Then put the gauge on the stock rails at the point end and solder there
Please be carefull here.  You need to solder on the outside of the stock
rails but not inside. Don't get any solder in-between the stock rails and the points.

Notice that the tie goes right at the end of the point rails to hold them at the right height

Now you should have this much done

Notice the gentle curves of the right point rail and the left stock rail.  They were curved
to match each other so the turnout will automatically be in gauge through the turn.
 

Now add the throwbar we made from a piece of .020 brass  .365 long by .050 wide
soldered in the center of a pc tie.  I used a razor saw to cut the gaps in the tie at each end of
the brass.  It's easier to do it now. Unless your going to use DCC and then these gaps
aren't necessary.

Tuck the base web of the points under the little bent up ends of the brass.
OK solder in the throwbar. This time solder each brass end to the side of
the point rail and don't get any solder between the stock rail and the point rail.

Puttin on the gaurds ..............................
Not so tough just line them up at the edge of the tie across from the end of the wing
rail ends. If you used exact measurements (R.E. gauges) then you can put the gaurd
rail right up against the stock rail. Remember to have bent the little ends first.
   [hint:  put another pc tie loose under the other end of the gaurd rails. Helps hold the right level]

 

ALLRIGHT now just check the flangeways through the frog and gaurds

 
 

Trim the ties ..... cut the remaining gaps   and you have a finished turnout.
Gaps ????? GAps????...

Well we gap differently and add one more tie if we want to do DCC.
 Regular turnouts you gap each tie in two places. Between each stock rail and each wing rail.
Even down in-between the point and stock rail on the throw-bar and the tie next to it.
That's eight gaps. Here is a regular T.O.

 

 For DCC, we add another tie. in the middle like this. and gap like this.
And then cut the two wing rails between the two center ties. (I use a dremel from the bottom)

Well we're ready to go to the RR and put in the Turnout.
Tomorrow on day 5.

Questions???? Send them to Hatch@RailwayEng.com

-Stephen Hatch

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From Boone Morrison:
> Not sure if you have ever gone into this, but how come one does not use the
> TRACK pin gauges on the NMRA, but the FLANGEWAY instead?  Is there some
> tolerance built in to the gauge that throws it off??  You have noted this
> approach before and I have been doing it ever since (with somewhat improved
> operation, though my previous ones run great too) but really don't know why
> you suggest this.
 

  The track end of the gauge allows too wide of track. The extra slop lets your
wheels wander from side to side. The normal track doesn't much matter but when
you go through the frog/gaurd area, the wheels must be lined up or they will
"bump" one side or the other. This little "jostling" is enough to cause a
problem on wheel sets that aren't "perfectly" round and concentric. (most)

  So by using the flangeway end as a gauge, you get the exact gauging that lines
up the wheels to pass through the frog/gaurd without "bumping" ...thus smoother.
There is absolutely NO REASON to use the sloppy gauging of the NMRA gauge. Especially
when the correct track width is on that same gauge .... just at the other end.
  The NMRA track width allows a prototypical 2inches TOO WIDE. We don't need this.
So just use the other end (called flangeway) to set your rails and VOILA .. smooth track.
-Steve Hatch
 

Question:
>How would I modify Hatch's tutorial on handlaid turnouts for making a
>curved turnout? Given a mainline radius, how do you determine what
>turnoff radii and frog angles are possible? Where are the two curves
>tangent? at the tip of the points? Should the points be curved? Is the
>frog itself straight. I imagine with a drawing of the turnout as a guide and answers
>to these questions, making a curved turnout should be the same as making a straight one!

.. Your correct. A curved turnout is curved all the way. Points, frog etc. Just lay out some flex track on the curve you want. Masking tape a piece of paper (one edge only) next to the track ....laying over the track. with a pencil on it's side, trace the tops of the rails. Lay the paper back and now put the flex track in the second curve. lay the paper back down and trace the tops again in the second curve. This forms the turnout. Just copy these rails and you have your turnout.

-Steve Hatch

Question:

>In my calculations for turnouts, heel and toe are fixed lengths and the
>curve from toe to point is constant. Do you regard this thinking flawed?

Frog and points are incidental constructs in the overall curve of the
diverging route in a turnout.
That curve should be a constant from start to finish. Unfortunately, the
NMRA fostered the notion that some tangents were desired in this curve.
It's not true and the turnouts flow much more smoothly if the tangent idea
is thrown out. I'm not sure why such a bad engineering premise was ever
considered let alone adopted. Once the individual wheels are guided into the
curve, then they don't need to be jostled about with "straight" sections.
The NMRA also made the gauge much too wide at that time and the result is
excess derails because the wheels can turn sideways in the track and catch
on any flaws.
In the prototype, the turnouts that are low speed may indeed have a
bit of tangent in the design, but in a high speed turnout, no jostling
is allowed so the curve must be designed, built, and maintained in a
smooth curved flow from start to finish. This is a primary engineering
rule in flange/rail turnout construction. You can see that going from
curve to straight to curve etc. puts undue and dangerous pressure/wear on
the rail as it forces the trucks to pivot to each new direction.
This tangent removal also reduces derailments on our models.
-Steve Hatch

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